Rous returned to the family estate, Henham Park, for 12 months leave, but was ordered to rejoin his regiment in Brussels following Napoleon's escape from Elba in March 1815. While serving in Wellington's campaign in Belgium, Rous was wounded at Quatre Bras and so did not take part in Napoleon's defeat two days later at Waterloo.[3]

After the death his father in August 1827[7] he became the 2nd Earl of Stradbroke. He pursued an active life as a peer and politician,[3] also serving as the Colonel of the East Suffolk Regiment of Militia from 1830 to 1844,[6] and as Lord Lieutenant and the Vice-Admiral of Suffolk, 1844–1886.[3]